The "distributed amplifier" has been used for extremely broadband amplifiers and which have a flat frequency response from essentially direct current all the way to as high as several tens of gigahertz. The use of the distributed amplifier or traveling wave amplifier was reported by Edward L. Ginzton, et.al., in a paper entitled "Distributed Amplification" published August, 1948 in the Proceedings of the IRE. The concepts in that paper are useful background for the present invention and that paper is incorporated herein by reference thereto.
That paper mentions, on page 962 under the heading "Tapered Plate Lines" an impedance matching technique for a vacuum tube circuit which enables several distributed amplifier stages to be coupled to maximize the gain by properly matching the impedance from one stage to the next.
More recently, several articles have been published relating to distributed amplifiers and traveling wave amplifiers having an integrated circuit structure in keeping with the advance of technology in this area. However, a continuing problem exists with respect to having a major portion of the output power being dissipated through the dual termination construction of the present state-of-the-art. A paper entitled "A DC-12 GHz Monolithic GaAs FET Distributed Amplifier" by Eric Strid, et.al., published July 1982 in the IEEE Transactions on Microwave Theory and Techniques shows a method of manufacturing a state-of-the-art distributed amplifier. A second paper entitled "A Monolithic GaAs 1-13 GHz Traveling Wave Amplifier" by Yalcin Ayasli, et.al., published July 1982, IEEE Transactions on Microwave Theory and Techniques discloses again a doubly terminated technique wherein at certain frequencies, significant portions of the output power are diverted through the output termination and thereby approximately 50% of the output power is wasted.
To improve the understanding of the "image method" for filter design utilized in the above incorporated publications as well as in the present application, chapter 3 entitled "Principles of the Image Method for Filter Design" from a leading text in this area entitled Microwave Filters, Impedance-Matching Networks, and Coupling Structures by George L. Matthaei, et.al., is recommended as useful background and chapter 3, pages 49 to 81, of that text are hereby incorporated by reference.